Abstract #0402

Gruetter R, Ugurbil K, Seaquist E, Henry P, Oz G

[1-13C]glucose was infused i.v. in four healthy human volunteers for up to 50 hours in order to measure 13C label incorporation into metabolites with a low metabolic rate such as N-acetyl-aspartate (NAA) and glutathione (GSH). Our results indicate that the entire pool of NAA is metabolically active, and that the time constant for NAA turnover is about 30 hours in the human brain. Our results also demonstrate the feasibility of measuring glutathione turnover from glutamate in the human brain.